Various Tech.

Allowing users to have ssh access Hi Readers, It is one of the tasks we need to complete in order to allow users to log-in into your server without compromising your security. We are going to accomplish the following tasks, 1.) Allow the users for given domain only 2.) Must allow access to a given domain 3.) Block access for a specific domain. These questions are asked in RedHat certification examination RHCE6 We are going to complete the above mention task using iptables To give proper example we are taking 192.168.20.0/255.255.255.0 as our domain and 192.168.21.0/255.255.255.0 as other domain. Assuming that your system is a fresh installation we can remove all rules previously applied. # iptables -F  The above mention command will flush all the previously applied rules. Insert a rule in your input chain by below mention command, # iptables -I INPUT -s <ip of your domain>/<subnet mask> -p <protocal tcp/udp> --dport <port> -...

Yum Configuration Hi Friends, we all have faced problems while configuring yum in RedHat, Fedora and Centos. Please find the below mention steps to use all the RPM packages come along with your distribution. Yum configuration will allow you to use them with proper dependency resolution. To configure yum you must have two packages, 1. yum 2. createrepo To obtain the same do the below mention just after you have mounted you disk. There could be two conditions a.) You have the distribution disk i.e. DVD. Please follow the below mention instructions to manage the same. Your system mush have the greater or equal space of DVD. # df -ah User the partition which has the space and create a directory. In my case /mnt has the space. # mount /dev/dvdwriter /mnt # cd /mnt/Packages/ # rpm -ivh yum-* --nodeps –force # rpm -ivh vsftps* -y # rpm -ivh createrepo* --nodeps --force # cp -rpvf /mnt/* /var/ftp/pub It will create the dump on /var/ftp/pub now we need to unmount the disk. # umount /mnt b.)...

1.Use the interpreter for bash at first line . #!/bin/bash 2. Use variables as per requirement and pass it to except if needed. HOST="localhost" USER="chitti" PASS="123" CMD=$@ 3. Use expect script as required. XYZ=$(expect -c " spawn ssh $USER@$HOST expect \"password:\" send \"$PASS\r\" expect \"\\\\$\" send \"$CMD\r\" expect -re \"$USER.*\" send \"logout\" ") 4.Print the result of except using echo like echo "${XYZ}"

Send Mail to gmail account with perl Installation of Send::SMTP::Gmail:  In order to send mail via Gmail, you need to have TLS verification. Having TLS and Installation of perl package Send::SMTP::Gmail is covered in brief.  For Ubuntu:  sudo apt-get install openssl libnet-ssleay-perl  libcrypt-ssleay-perl For RedHat/Fedora/CentOs: yum  install  perl-IO-Socket-SSL  perl-Digest-HMAC  perl-TermReadKey  perl-MIME-Lite  perl-File-LibMagic  perl-IO-Socket-INET6 perl-Net-SSLeay perl-Crypt-SSLeay perl-Email-Send Usages:  Following method is used to send mail and attachment in it. Please read it and post your comments. sub sendMail {         use Email::Send::SMTP::Gmail;         my $to=shift;         my $cc=shift;         my $subject=shift;         my $body=shift;       ...

I've used a few techniques for this kind of reading but gets failed until I've read this fine blog . http://www.bashguru.com/2010/05/how-to-read-file-line-by-line-in-shell.html this helps a lot and i have developed a trick for me. Refer to the following example to examine the script : #!/bin/bash #SCRIPT: method2.sh #PURPOSE: Process a file line by line with redirected while-read loop . FILENAME=$1 count=0 while read LINE do let count++ echo "$count $LINE" done < $FILENAME echo -e "\nTotal $count Lines read" I have passed the file in the end of the loop so i didn't need  to use pipe that is why i process the file in fastest manner and gives  the required output in a quick manner. However i can use one more thing the File Descriptors. The File Descriptors are similar to the normal file pointers however in  more analogue way.If you have used C then you will have familier with the  the default file openers in C "st...

Edit your Publish settings for Flash SWFs and HTML to reflect how you want your Flash SWF to appear in your web page. Export your Flash movie as HTML. Locate your HTML file on your computer, right-click, and select "Open With". Choose either NotePad or another text editor. Copy the source code from the HTML file. Paste it into your web page's source code in the appropriate location where you want your SWF file to display. Edit the file path to reflect the location of the SWF file on your web server, and upload both your HTML and SWF file to the appropriate directories on your server. ( Note:  this also applies if you're using PHP, JSP, ASP, CGI, or other web page extensions.) Your code should look something like this: <OBJECT classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" WIDTH="320" HEIGHT="240" id="You...

In MySQL user always tries to connect with the server via command line interface such as remote login like 'ssh' then they troubled themselves in using graphical interface and get the required output quickly. So they need to automate that task. In this Blog I am going to suggest you a way to do this ... First of all we need to know that a MySQL service is kept in /etc/init.d/mysqld and we need to invoke that in order to use mysql server and client. To do this use following command in terminal : service /etc/init.d/mysqld start or service mysqld start When mysql server is started make a directory like /home/anduril/shubham_Script and after entering into that directory use this command in your terminal. vi connect_string.sh It will create a file with the name connect_string.sh you can give any name you want. Press 'i' to edit and enter the following text : mysqlshow -u root -proot mysqladmin version -u root -proot mysqladmin variables -u root -proot mysqladmin ping -u roo...

The command sudo provides other users to run a command as a root. To use sudo user must have their level of privilege in /etc/sudoer file. In some cases this file is set for read only and others can edit that file and add their user name in Sudoer for this case such as Fedora 12 users need to provide this syntax as a root on their terminal. Syntax for adding a user in Sudoer file is: echo "username ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers And to gain the writing privilege you can use the following code in your terminal : chmod 755 /etc/sudoers This code will be enough to give permissions to the user and his user group. If you are an ubuntu user you can easily add your user in this file like: vi /etc/sudoers And you will get a text file. Afterward you need to press 'i' for edit and edit by adding your username just below "root ALL=(ALL) ALL" "username ALL=(ALL) ALL"

Start mysql in Ubuntu without having root privilege:- If you want to use mysql in Ubutu you can use following command which will use a root level privilege   $ mysql -u root -p Enter password: Welcome to the MySQL monitor.  Commands end with ; or \g. Your MySQL connection id is 147 Server version: 5.1.49-1ubuntu8.1-log (Ubuntu) When it demands to enter the password fill it with 'root' and hopefully you'll get logged in .   Last_insert_id():- (with no argument) returns the first automatically generated value that was set for an AUTO_INCREMENT column by the most recently executed INSERT statement to affect such a column. For example, after inserting a row that generates an AUTO_INCREMENT value, you can get the value like this:   mysql> SELECT LAST_INSERT_ID(); Database():- Database() method returns the current selected database and you can use it in your communication and your queries. The syntax is :   mysql>select Database (); User():- It a...